2837xd code generation module learning (3) -- IIC, ECAN, SCI, watchdog, ECAP modules

Model links ： link

1 IIC modular

1.1 Model function

  Implementation to address 0x50 Write data from the slave (100 ,1), Then detect when the written data changes , Begin with （ The slave address is 0x50） Space to read the data just written .

  It can be seen that the above figure is mainly divided into three parts ：1. Definition of global variables .2. Write data .3. Reading data .

1. Global variables are defined using Data Store Memory modular , There is also Data Store Write and Data Store Read The module is used to read and write the open space , Its Data Store Memory Set as follows ：

2. The write data sub module is shown in the figure below , What we use here is Enable Subsystem, And Trigger Subsystem The difference is Enable Subsystem yes Level trigger and Trigger Subsystem yes edge-triggered . Here is to splice the data and address, and then give Transmit Module to send .

3. The read data module is sent to the device address , then do…while Wait in the loop I2caRegs.I2CFFTX.all The sign is ready （TXFFST The length of received data will be displayed in ）, Then enable the receiving module to receive data , Then store the data in global variables A and B in

do…while Situation in the module ：

2 eCAN modular

eCAN The module is divided into receiving module and sending module , The parameters of the receiving module are as follows （ At present, enter the receive interrupt service function to execute , There's something else .）：

eCAN The receiving module comes with an interface that triggers the execution of a function , In modeling , I connected to a LED Flipped sub modules . That is, after receiving the message ,LED It's going to flip .

eCAN The parameters of the sending module are as follows , because CAN The largest data frame is 8 Byte length , So we must pay attention that the largest data given to him is an unsigned 64 A data .

  Here, the ports for data transmission of octet transmission and four byte transmission are built . Pay attention here , Need modification Constant The output type of the module .

After that, it needs to be in Configuration Parameters Chinese vs eCAN_A Make relevant settings :

2.1 experimental result

  The hardware used here is USB turn CAN, The software is CANTest The test conducted by the upper computer , You can see the sending ID by 0x01 The data of ,dsp After receiving LED Flip . Then the observation data is big / This point of the phenomenon of small end storage needs attention . The data format can also be clearly seen in the serial port debugging assistant , Starting standard + Data length +ID+ The format of the data .

3 SCI modular

The interrupt function is SCIA Interrupt service number of ：9.1. The interior is as follows

This is achieved SCI Receive interrupt , Return the sent data .

SCI The module also has two modules, receive and send ： Receiving module configuration ：

Send module configuration ：

After that, it needs to be in Configuration Parameters Chinese vs SCI_A Make relevant settings :

3.1 experimental result

You can see that the sent data can be returned normally .

4 Watchdog module

  The watchdog module can effectively prevent the program from flying in the actual program . stay Simulink You need to start with Configuration Parameters The relevant settings are made in , The cycle in the figure below is the watchdog overflow time （ That is, if there is no dog feeding operation within this time , Will reset the entire system ）.

Corresponding in Simulink There is ,Watchdog modular （ For feeding dogs ） Here the -1 It means the same as the simulation step time . Dog feeding time can also be set here , However, it must be noted that the dog feeding time must be less than that in Target hardware resources Time set in , In this way, it is normal to feed dogs .

5 eCAP modular

  eCAP The mode is input capture module , It can be used to test the signal cycle and other information . It can also be used as APWM Mode output PWM wave .

Pictured above , stay Configuration Parameters Can be set in eCAP Patterns and APWM Pins of the model .

5.1 APWM Pattern

Make corresponding settings in the tab .

experimental result ：

5.2 eCAP Pattern

The tab can be set as follows , At this time, the module has an output interface TS, If set as shown in the figure , The first time to capture the rising edge , Second capture falling edge , Capture the rising edge for the third time . That is, the duty cycle of the square wave signal can be calculated . Then output is directly utilized DeMux The module can get the counter array of three times respectively , Array times TCLK Get time .